Physical fitness, body fatness, and physical activity: The Amsterdam Growth and Health Study

The purpose of this study was to examine sex-specific longitudinal relation ships between physical fitness (cardiopulmonary and neuromotor fitness) and body fatness (sum of skinfolds) and to examine the influence of physical a ctivity (weighted activity score) on these relationships. The data were obt ained from the Amsterdam Growth and Health Study (AGHS), an observational l ongitudinal study of 98 females and 83 males, with six repeated measurement s over a period from 13 to 27 years of age. The longitudinal relationship b etween body fatness and physical fitness was analyzed using generalized est imating equations (GEE). For each of the eight fitness items used as outcom e variables, standardized regression coefficients were calculated for the r elationships with body fatness and for the relationships with physical acti vity with and without correcting for height and weight. In all analyses, bo dy fatness was inversely related to running speed, standing high jump, leg lift speed, and maximal oxygen uptake. Physical activity was positively rel ated to leg lift speed and maximal oxygen uptake, and only in females to th e standing high jump. Thus, body fatness is inversely related to most fitne ss items, while physical activity is positively related to only several fit ness items. Further, body fatness and physical activity are independently r elated to physical fitness. (C) 2000 Wiley-Liss, Inc.